The cellulase of Trichoderma koningii. Purification and properties of some endoglucanase components with special reference to their action on cellulose when acting alone and in synergism with the cellobiohydrolase

Publisher Website
Google Scholar
Abstract
Four principal endoglucanase components of T. koningii cellulase were separated and purified by gel filtration on Sephadex G-75, ion-exchange chromatography on DEAE- and sulfoethyl-Sephadex and isoelectric focusing. All 4 endoglucanases hydrolyzed CM[carboxymethyl]-cellulose, H3PO4-swollen cellulose, cellotetraose and cellopentaose, but differed in the rate and mode of attack. Attack on cotton fiber by the endoglucanases was minimal, but resulted in changes that were manifested by an increased capacity for the uptake of alkali, and a decrease in tensile strength. All 4 endoglucanases acted synergistically with the exoglucanase [cellobiohydrolase] of T. koningii during the early stages of the breakdown of cotton fiber, but only 2 could produce extensive solubilization of cotton cellulose when acting in admixture with the exoglucanase component. The mode of action of the enzymes is discussed in relation to these synergistic effects. The interpretation that the crystalline areas of cotton cellulose are hydrolyzed only by those endoglucanases capable of forming an enzyme-enzyme complex with the cellobiohydrolase on the surface of the cellulose was supported.